Polymerization catalyst compounds are typically combined with an activator (or co-catalyst) to yield compositions having a vacant coordination site that will coordinate, insert, and polymerize olefins. Typically, methyaluminoxane (MAO) is utilized to activate metallocene catalysts. Alternative cocatalysts for metallocenes and other single-site polymerization catalysts have been discovered in recent years.
It is known that perfluorophenyl aluminum and borane complexes containing one anionic nitrogen containing group may activate metallocenes. For example, R. E. LaPointe, G. R. Roof, K. A. Abboud, J. Klosin, J. Am. Chem. Soc. 2000, 122, 9560-9561, and WO 01/23442 A1 report the synthesis of (C6F5)3Al(imidazole)Al(C6F5)3][HNR′R″]. In addition, G. Kehr, R. Fröhlich, B. Wibbeling, G. Erker, Chem. Eur. J. 2000, 6, No.2, 258-266 report the synthesis of (N-Pyrrolyl)B(C6F5)2.